@Jason because it's expensive if you just need a color.
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AndyJun 20 '14 at 19:33

@Andy This is (or maybe, and hopefully was) the only way to get semantically correct color. Others are all semantically wrong. Though most people just can satisfy with approximated result, but still it doesn't mean that's correct.
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EonilJun 21 '14 at 2:46

@Eonil too bad separatorColor is not UIAppearance compliant, otherwise it might be easier to get. I agree with you regarding approximation, but you might not even notice any difference on screen. In a long shot your solution is next OS ready if Apple changed a color scheme.
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AndyJun 27 '14 at 14:37

@Andy Yeah, I agree that color change is unlikely to happen, and the app would be updated before the SDK changes.
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EonilJun 27 '14 at 14:56

To find out any colours on your iOS device, just run the app in the Simulator then use Apple's DigitalColor Meter (in your utilities folder) and hover over the colour you need info on. Alternatively just do a screen grab from the phone, open that in Preview and use DigitalColor Meter to read the colour values.